Hoist.



UNITED STATES PATENT OFFICE.

LOUIs D. ROUND, OE CLEVELAND, OHIO, AssIGNOE To DAVID ROUND AND sON, OE CLEVELAND, OHIO, A PARTNERSHIP.

HOIST.

SEECIFICATION forming part of Letters Patent No. 721,968, dated March 3, 1903.

Application iilefl` October 9, 1902. Serial No. 126.418. (No model.)

To all whom it may concern,.-

Be it known that I, LOUIS D. ROUND, acitizen ofthe United States, residing at Cleveland, in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Hoists, of which the follow-` ing is a full, clear, and exact description, reference being had to the accompanying drawings.

1o The invention relates to hoistsin general, and particularly` to that type wherein the chain-wheel shaft is provided with a wormwheel and a Worm-screw is arranged to rotate said worm-wheel.

The object of the invention is to reduce the friction incident to turning the worm-screw, and thereby to enable the hoist to be operated by less power.

The invention consists, primarily, in the zo construction and combination of parts hereinafter shown in the drawings and set forth in the specification and claims.

Referring to the drawings, Figure l is a side elevation of a hoist similar to what isV z5 known as a Harrington hoist. Fig. 2' is a vertical section through the gearing. Fig. 3 is a front elevation of the bearing-adjusting ring, and Fig. 4 is a detailed View of the parts associated about said ring.

3o Referring to the parts by letters, A represents the casing in which the operating-worm is rotatively mounted and which incloses the worm-wheel which is keyed to the chainwheel shaft B, also mounted in said casing.

3 5 0.2 represents a retaining-plate for holding the worm in place, while in the upper end of the casing is a supporting-hook B', which is pivoted upon a pin b.

Upon the end of the shaft B is a chain- 40 Wheel D, carrying the hoisting-chain E.

In the inner end of the recess a in the casing the bearing-cup H2 is secured, while upon a reduced end portion f3 of the worm-shaft F a cone-cap H is fitted. Suitable balls are arranged between it and said cup. A shoulder f2 is formed on the worm-shaft for the purpose of serving as an abutment for a cone J ,Which is fixed upon said shaft. The wormshaft F passes out of the casing through the 5o plate a3. Between this plate and the cone J is the cup J2, between which and the cone J is a raceway for balls J. This cup may be adjustably secured to the casing in any suitable manner. Preferably it has an outwardlyextended cone-like end J2, which enters an annular recess k in an adjusting-ring K. This ring is fitted to the recess in the casing, and it embraces the worm-shaft, along which it may be moved eudwise. In the outer face of this ring are three recesses k, more or less, 6o into whichV the inner ends of the adjustingscrews L project. These screws screw through the plate a3 and by bearing against said ring properly adjust the pressure on both sets of balls. The rotation of the ring K is prevented by the engagement of the screws in said recesses. It will of course be understood that the cup J2 and ring K may be in one piece; but there is this advantage in making them separately-viz. it is easier and less eX- 7o pensive to harden the cup. That is also the reason why the cone H is made independently in the form of a cup fitting the end of the worm-shaft. When several screws are used to adjust the tension on the balls, one may by screwing one in farther than the others put a greater pressure on one side of the axis than the other. If this is done, the cup J2, because its cone-shaped end is fitted into a recess in the ring K, will automatically ad- 8o just itself so as to equalize the pressure.

Having'described my invention, I claiml. VIn a hoist, the combination with a casing containing a recess which is closed at one end,

a worm-wheel which is mounted in said cas- 8 5 ing, a worm coperatin g therewith and mounted in said recess, with a ball-bearing cup in the closed end of said recess, a cone on the worm cooperating with the cup to form a ballraceway, a second cone on said Worm near 9o the open end of said recess, a coperating cupgadjustably held in the open end of said recess and cooperating with said cone to form a ball-raceway, and antifriction-balls in said bal'l-raceways.

2. In a hoist, in combination with the casing, of a Worm -wheel mounted therein, a worm coperating with said worm-wheel and having a reduced inner end portion, a conecap upon said reduced end portion, a bear- Ico ing cup mounted in said casing, balls between said cone-cap and said bearing-cup, a

cone secured upon the shaft of said worm, a bearing-cup supported by the casing, balls between said bearing-cup and said cone, and means for adjusting said cup, substantially as specified.

3. In a hoist, in combination with the casing, of a Worm -Wheel mounted therein, a Worm coperating with said Worm-Wheel and having a reduced inner end portion, a conecap fitted upon said reduced end portion, a bearing -cup mounted in said casing, balls between said cone-cap and said bearing-cup, a second cone secured to the worm-shaft, a ball-bearing cup having a cone-like eXtension, an adjusting-ring having an annular recess to receive said extension, and means for adjusting said ring, substantially as described.

4. In a hoist, in combination with the casing, of a worin-Wheel mounted therein, a Worm cooperating with said Worm-Wheel and having a reduced inner end portion, a conecap upon said reduced end portion, a bearing-cup mounted in said casing, balls between said cone-cap and said bearing-cup, a second cone secured upon the Worm-shaft, a bearingcup having a cone-like extension, an adjust.- ing-ring having an annular recess in its inner face, and a plurality of recesses in its outer face, and screws in the end of the casing for engaging in the last-named recesses, substantially as described.

In testimony whereof I hereunto ax my signature in the presence of two witnesses. LOUIS D. ROUND. Vitnesses:

E. L. THURsToN, E. B. GILCHRIST. 

